Improvement in the manufacture of steel



- 2-Svheets--Sheet1l J. e. BLuNT.

` Manufacture of Steel.

No. 137,885. PatemedAprllsnes.

A Zwaar AM. man1/mammie 0o. lul/.(osaamsfs mams) 2 Sheets--Sheet l2.

Patented Apri! 15, 1873.

1.G.BLUNT.

Manufacture of Steel.

E, I E

my j.

UNITED STATES PATENT OFFICE.

JAMES G. BLUNT, OF LEAVENVVORTH, KANSAS.

Y IMPROVEMENT IN THE MANUFACTURE OF STEEL.

Specification forming pai-tof Letters Patent No. 137,885, dated April l5, 1873; application filed 'April 5,1873.

To all whom it may concern.-

Be it known that I, JAMES G. BLUNT, of the city of Leavenworth, in the county of Leavenworth and State of Kansas, have invented a new and useful Improved Method of Manufacturing Steel, by the use of petroleum or fixed-carbon gas, with or without the combination of superheated steam or fixed hydrogen.

This invention relatesl to puddling-furnaces and consists in the construction of the same and the novel arrangementof devices, whereby petroleumfvapor or fixed hydrocarbon-.gas,with or without superheated steam or free hydrogen, is used as a fuel in such furnaces. The object of this invention is to manufacture steel direct from the pig or cast iron, and of superior quality, and at a much less cost than by any other known process, byreason of paddling or decarbonizing the metal with the petroleumvapor or pure hydrocarbon flame, whereby all sulphur and other impurities are decomposed, eliminated, and driven o" in the form of vapor, and after which the metal or iron, while in its `molten state, is injected or charged with petroleum in vapor, or carbongas, which immediately becomes diffused throughout the mass of metal, carbonizing the same to any desired extent, and converting it into steel.

I am aware that steel has been made direct from pig or cast iron by the forcing of carbon through the metal in the form of pulverized charcoal, and also by burning out the carbon from the metal by forcing air through the molten mass and its recarbonization by the introduction and mixture of spiegeleisen; but in such processes it is difficult to obtain perfect uniformity in the grade of steel in the same charge, or similar grade and quality from different charges, requiring an expert in the use of the spectrum vto conduct the operation; while by the process of this invention the pure carbon, in form of petroleum-vapor or xed gas, is introduced and uniformly distributed at the proper time, and under any desired pressure,

and, by being passed through a meter, may be so regulated as to inject any certain lquantity of carbon into a given quantity of metal, and thereby making any desired grade or quality of steel and producing any number of charges of the same uniform grade.

To enable others to construct and operate my invention, I will proceed to 'describe its construction and mode of operation, reference being had to similar figures and letters ofthe accompanying dra-wing, in whichj Figure l represents a vertical section of the furnace. Fig. 2 represents a horizontal section on line w w. Fig. 3 is a plan view with the heating=chamber in section. Fig. 4 is a horizontal section on line y y. f Y

In the drawing, A represents the oven for melting and boiling the metal, which is of an oval and elongated form. B represents a combustion-chamber or nre-flue at either end of the furnace. These combustion-chambers extend upward in a vertical line to a point on a line with the bottom or hearth of the oven A, then contracting and tapering as they traverse in a curved line upward and inward to the narrow opening a into the oven of the furnace. E represents a chamber above the roof of the oven `A for heating the air in the pipes b b. In each of the four corners of the roof of the furnace proper is an opening or ue for the passage ot' the flame from the oven A, which ame, pass` ing around the air-pipe b b, passes of through the stack or chimney f. C represents the pipe for the introduction of the petroleum-vapor or hydrocarbon-gas through the wall of the furnace O into the combustion-chamber B, termii natin g in a cross-head, e, provided with jets or burners d. b b represent a large iron pipe or flue for conveying and heating the air. This ue, after passing through the wall and entering the chamber E, doubles back and forth within the said chamber over its whole extent, and then, bifurcating or dividin g into two flues, conveys the air to the combustionchamber B. When superheated steam is used in conjunc tion with hydrocarbon, the ordinary steam is conveyed in a pipe, n, through the wall of the furnace at the side of the combustion-cha1nber B, until it reaches a point near the commencement of the curve in the bridge-wall of the furnace D, and then passes backward and forward in a number of folds or convolutions, fm, on said bridge-wall (protected from the intense heat by a thin layer of tire-brick or clay,) and thence back through thefurnace-wall and into the combustion-chamber B, terminating in cross-heads and jets z just above the gas-burners.

U represents the frame-work of the furnace.

N, Fig. 2, represents the doors provided for obtaining access to the interior. His a gas-pipe, which passes through the wall of the furnace and extends around the oven above the level of the melted iron, and within the furnace-walls so as to beprotected from the action of the great heat, and from which a number of small pipes or jets (made of plumbago or other re-proof material) project downward and inward, and terminate in the ovennear its bottom or hearth, and through which the petroleum-vapor or carbon-gas is introduced directly into the molten matter.

The operation of my furnace is as follows: The air-blast being turned on, the valve in the gas-pipe c is opened and the petroleum vapor lor hydrocarbon is ignited in the combustionchamber B, which, in combination with the air `from the blast, produces an intense and pure iiame, which passes through the throat ofthe flue a, in a broad and narrow sheet, into the oven A. When Vthe oven is sufficiently heated it is charged with pig or cast iron, which is melted, boiled, and puddled in the usual manner. After the molten metal is sufficiently puddled and manipulated to decarbonize it and free it from its impurities, and when in that -state 'in which the slag or cinder is about to separate from the iron, the air-blast is turned off from the furnace and sufficient petroleum vapor or gas admitted into the oven A to prevent the admission of air, while, at the same time, the valve admitting the petroleum vapor or gasinto the gas-pipe H is opened, and the vpetroleum vapor or gas is thus introduced through the small pipes or jets directly into the mass of molten metal in any required quantity, and, by this direct introduction of petroleum vapor or gas, carbonizing the metal to make any grade of steel desired, after which the mass is balled and treated in the usual manner with the squeezers or hammers and rolls, and the furnace again charged with pigiron, and thus the operation repeated.

When superheated steam is used it is taken from any steam-boiler, and, passing through the pipe u and the superheater m, is conveyed vto the combustion-chamber B, and there mixed with the petroleum vapor and air; but the more -pr'eferable manner to use superheated steam is to first pass the same from the superheater m through a retort filled with charcoal and heated to such a degree as to combine the oxygen of the steam with the carbon of the c oal, forming a carbonic oxide and freeing the hydrogen, and using the same in the form of a fixed hydrogen gas, which prevents the oxidation of the metal,'which might otherwise occur in the useA of simple superheated steam.

The petroleum-vapor or hydrocarbon to be used in this furnace may be produced by any suitable generator in use for that purpose, and the steam from any ordinary steam-boiler, while the air-blast can be supplied by any well-known apparatus. v a

Having thus described my invention, what I claim as new, and desire to secure .by Letters Patent, is

l. The gas-pipe H and connections, in combination with the oven A, substantially as shown, and for the purposes set forth.

2. Superheater m, in combination with thc combustionchamber B, the gaspipe C, and air-fines b b, substantially as shown, andv for the purposes set forth.

3. The heating-chamber E, in combination with the oven A, the air-fines or pipes b b, and the stack f, substantially as shown, andfor the purposes set forth.

4. The process of manufacturing steel from pig or cast iron, the same consisting in boiling or puddling the iron to a point at or near what is known as coming to nature, and then ,re carbonizing and converting the same into steel by means of petroleum-vapor or hydrocarbongas, substantially as set forth.

JAS. G. BLUNT. Witnesses:

J. L. PENDERY, T. G. BREcH'r. 

